Treatment of felt and felt-hat bodies



Patented Sept. 24, 1929 1,729,474

' UNITED STATES PATENT OFFICE ERICH noun, or VIENNA, AUSTRIA TREATMENTOF FELT AND FELT-HAT BODIES No Drawing. Application filed september 2,1926, Serial No. 133,298, and in Austria June 1, 1926. Modern chemistrymakes a neat distincdrolysis. Thus for instance by neutralizing tionbetween metal compounds of the first chromium alum or chromium sulphateit is order 'thatis to say compounds in the molecule not chromiumhydroxide Cr,(OH) that isof which a metal is directly combined withdirectly obtained buta series ofintermediary i a plurality of atoms ofother atoms all of compounds namely:

which are of equal nature, and metal compounds of a higher order that isto say com- Cr4(OH)2(SO4)5 Cr4(OH)4(SO4)-= pounds the molecules of whichresult from down to Gr,(OH), SO and thereafter chrothe combination of aplurality of molecules mium hydroxide Cr, .(OH) is precipitated in l ofcompounds of the first order. the form of a gel. 0 An example of acompound of the first order These metal compounds of a higher order isstannic chloride, SnCl, while an example or complex metal compoundsfrequently form of a compound of the second order is pink. colloidalsolutions as for instance the chrosalt min? compounds just referred to.

s I ave discovered that the a ueous solu- (NH4)ZSH('I QNHC1 S1101" tionsof metal compounds of a higher order or and an example of a compound ofthe third complex metal compounds as above defined order is preparingsalt or sodium stannate have tilelal property of increasing the lustrleof anima air more articularl of wool lair NflzSMOH) 6 2N3OH+SHO2+2H2Oespecially if the solutions are colloidal, and Such compounds of ahigher order are parmany of thes c mpl x m tal compounds are ticularlyreadily formed by metals electroknown to be tanning agents, that is tosay negative to aluminium and electro-positive to any agents capabl fhardening animal 1- mercury and having a small atom volume and la nousub ta Now y invention cona comparatively high atomic combining c sistsin treating felt and felt hat bodies with pacity such as, iron, zinc,cobalt, nickel, copheavy metal compounds of higher order or p81, tin,bismuth and before all the metals Of complex compounds of heavy metalsby apthe chromium group, namely chromium, tungplyin aq ou s luti ns of sch compounds sten, molybdenum and uranium. Examples to the felt or felthat bodies separately or in of such compounds of higher order, or asthey any stage of their manufacture such as brushare often calledcomplex compounds are the ing or bl ki g metaltungstates, as [OW(VVO ]Kthe The following is a description of several metal ammines for instancehexammino-coexamples of carrying into practice my invenbalti chloride[Co(l lH,) ]Ql and its prodtion:

uctsof substitution. for instance triaquo- 1. I prepare a chromiumtanning liquor 8 triammino-cobalti-chloride by neutralizing a normalchromium salt for [CO (H O) (NH) 1C] instance chromium alum such tanmngliquor 2 a a s 3 containing about 0.5 to 1% of chromium.

or monochloro-1 entammino-cobalti-chloride This tanning liquor has stillto contain about F H HJH] in which the groups com- 0.1% of sulphuricacid which may be secured bined with potassium or chlorine respectivelyeither by neutralizing the chromium salt only appear to be selfconsistent radicles which do to the limit indicated or by addlng to allquor not undergo any change if these complex more completelyneutralized, a sufliclent quanchlorides are converted into nitrates,sultity of sulphuric acid or chromium alum. ph ates, carbonates and thelike. The presence of the small quantity of ac d has To these compoundsofhigher order or com for its object to prevent the preclp tation ofplex compounds also belong the so called basic chromium hydroxide on thehair which would chromium salts of very complicated c0nproduce greenspots on the felt. stitution formed in neutralizing chromium Thistanning liquor is heated to about 70 to compounds split up to a greatextent by hy- 80 centigrade and the felt hat bodies are placed into theliquor and left therein under slow agitation for about A; to 2hoursaccording to the quality of the felt. The hat bodies are then taken outand thoroughly rinsed. They have then a beautiful lustre and show a silklike firm hair. They can then be dyed and further treated in the usualmanner.

The chromium tanning liquor may also be prepared by the reduction methodused by tanners in which a concentrated solution of potassium bichromateand sulphuric acid is reduced by glucose, glycerine, or sulphur dioxide.The green solution contains the chromium compounds of higher order orcomplex chromium compounds but their percentage varies according to theconditions of reduction and therefore the effect on the felt is somewhatuncertain and besides the felt is liable to be discoloured. Also thecommercial chromium tanning liquors or salts may be used.

2. The velour felt hat bodies are placed into a solution of pink salt(NI-I SnCl,,, containing about 1 to 2% of tin and about 0.1 to 0.3% ofsulphuric acid and kept there under slow agitation at a temperature of 70 to 80 centigrade for to 2 hours according to the quality of the hatbodies. The latter are then rinsed and dyed in the usual way.

3. The felt hat bodies are placed into a 1% solution of preparing salt,Na Sn(OI-I) G and 0.5 to 1% of peroxide of hydrogen at a temperature of7 0 to 80 centigrade and kept there under slow agitation for to 1 hour.I Thereby the aspect of the felt becomes smooth and leather. like andvelour felt hat bodies acquire a high lustre. The addition of peroxideof hydrogen is necessary for preventing the discolouring of the felt,taking place in alkaline solutions. In using this alkaline solution caremust be taken to avoid any injury to the felt which might result from aprolonged action of the felt.

4. I prepare an aqueous solution of a tungstate or molybdate soluble inwater and containing about 1% of tungsten or molybdenum and add theretosulphuric acid so that it contains 0.1 to 0.3% thereof. In the case oftungstate solutions the addition of 0.5 to 1% of peroxide of hydrogen isnecessary for preventing tungstic acid from being precipitated. Theneutral or acid solutions of tungstates or molybdates contain tungstenand molybdenum in the form of complex compounds orcompounds of a higherorder since the tungstates or molybdates of the first order K VVO and(NI-LQ MOQ can exist only in a strongly alkaline solution; thecommercial ammonium molybdate for instance has the formula (NH M0 0 plus41-1 0. The felt hat. bodies, more particularly velour felt hat bodiesare placed and kept therein for to 2 hours at a temperature of to 80centigrade under slow agitation. Thereby velour felt hat bodies having ahigh lustre are obtained which may be dyed and further treated in theusual manner.

The complex metal compounds as above defined may also be used forbrushing velour felt hat bodies or added to such brushing Water; theymay be also added to the blocking water. 1

I Wish it to be understood that I do not claim the use of potassiumbichromate nor the use of ordinary double salts such as potassiumaluminium alum.

What I claim is:

1. A process for treating felt and felt hat bodies for increasing thelustre thereof consisting in applying thereto an aqueous S0111? tion ofa complex compound of a heavy metal of the chromium group. i

2. A process for treating felt and felt hat bodies for increasing thelustre thereof consisting in applying thereto an aqueous solution of acomplex compound of chromium.

3. A process for treating felt and felt hat bodies for increasing thelustre thereof consisting in applying thereto an aqueous solution of acomplex compound of a heavy metal by placing the felt and felt hatbodies into an 1 aqueous solution of such complex salts and keeping themtherein at a temperature above room temperature and below the boilingpoint of water for some time under slow agltation.

4. A felt hat body having incorporated into its fibres an inorganictanning agent.

5. A velour felt hat body having incorporated into its hair an inorganictanning agent.

In testimony whereof I have aflixed my signature.

ERICH BGHM.

